1. Field of the Invention
The present invention relates generally to a fuel tank assembly and; more particularly, to a fuel tank assembly in which an instrument is releasably secured to the fuel tank by a reinforced retainer ring.
2. Description of Related Art
An automotive fuel tank assembly commonly includes a fuel tank having various instruments, such as vapor vent valves, pressure transducers, fuel senders, and the like, attached thereto. Often, these instruments are positioned such that they extend through openings in the fuel tank wall to communicate with both the inside and the outside of the fuel tank.
Various means for securing the instruments to the fuel tank are known. For example, it is known to attach a vapor vent valve to a plastic fuel tank by inserting the valve into a large rubber grommet positioned over an opening in the tank. The grommet envelops a portion of a plastic ring welded to the fuel tank wall around the opening and is thereby held in place over the opening. One drawback of this approach is that the large, irregularly-shaped grommet is a relatively expensive sealing mechanism. Another drawback of the approach is that the grommet must generally be lubricated to facilitate insertion of the valve.
A second approach for attaching a vapor vent valve to a plastic fuel tank is disclosed in U.S. Pat. No. 5,139,043. The patent describes a vapor vent valve that is directly welded to the outer surface of the fuel tank wall. While this approach eliminates the need for a grommet and the problems associated therewith, a welded valve is, nevertheless, undesirable from a servicing standpoint.
A need therefore exists for a fuel tank assembly having retaining and sealing means for securing instruments to the fuel tank, which means are not only reliable and low in cost but which also enable the instruments to be easily removed from the fuel tank for servicing.